20
jejune(noun, adjective, set, weak, kind)
20
ordinary(adjective, common, boring, usual, commonplace)
20
sombre(adjective, characteristic, unhappy, dark, property)
19
apathetic(adjective, calm, quiet, tough, flat)
19
colourless(adjective, characteristic)
19
inert(adjective, upset, quiet, moving, flat)
19
listless(adjective, calm, quiet, bad, weak)
19
unsurprising
18
grey(adjective, leaden, steely)
18
languid(adjective, quiet, weak, flat, weakness)
17
half-assed
17
dim-witted(adjective, simple, slow, foolish, stupid)
17
obscure(verb, adjective, quiet, clear, weak)
17
pale(verb, adjective, quiet, beat, reduce)
17
slack(adjective, quiet, increase, weakness, low)
17
slow-witted(adjective, simple, ability, slow, stupid)
17
unimaginative(adjective, simple, tough, flat, excite)
16
muffled(adjective, quiet, weak, soft, gentle)
16
murky(adjective, obscure, dark, gloomy, dirty)
16
overcast(verb, adjective, clear, obscure, dark)
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APASmart Define. (2016). dull thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/dull/thesaurus/synonyms
ChicagoSmart Define. 2016. "dull thesaurus" https://smartdefine.org/dull/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, dull thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/dull/thesaurus/synonyms>.
MLASmart Define. "dull thesaurus" 29 March 2016. Web. 22 September 2026. <https://smartdefine.org/dull/thesaurus/synonyms>